<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        
        /* ul p{
            color: pink;
        } */
        /* ul>li>p{
            color: red;
        } */
        /* 父元素>子元素选择器  空格的后代选择器 */
        /* .li2 + .li3{
            border: 1px solid pink;
        } */
        /* 兄弟选择器 */
        .li2~li{
            border: 1px solid #ff0;
            width: 100px;
            height: 20px;
            background: #ff0
        }
    </style>
</head>
<body>
    <ul id="list">
        <li><p>1</p></li>
        <li class="li2">1</li>
        <li class="li3">1</li>
        <li>1</li>
        <li class="li3">1</li>
        <li>1</li>
        <li class="li3">1</li>
        <li>1</li>
        <li>1</li>
    </ul>
</body>
</html>